Poor Youtube Quality Upon Upload

[JohnSmith1981]

I am attempting to create a narrated YouTube video. Here is what I did:

1.) I created the PPT
2.) I imported the screen shots of the PPT into Windows Movie Maker
3.) I narrated the screen shots
4.) I saved the movie via Windows Movie Maker into the highest quality video format
5.) I uploaded to YouTube only to have the video all of a sudden go VERY grainy and low quality when it is full screen.

Any ideas? I've tried everything I can think of in increasing the quality of the screenshots, video resolution upon saving, etc. In my research, I found out about &fmt=18 but I need the default YouTube video to be high quality?????

[minidv2dvd]

i've never used wmm so i have no idea what it makes as "highest quality", but you need to go by youtube's definition of high quality to get the HQ or HD links for your video. HQ is usually 480p->720i at over 4mbps, HD is 720p or better at over 4mbps. less than 10min., and under 1 GB.

post a screenshot of gspot or mediainfo of your source video.